I really don´t know how to read that image but hope for the best for sure.
Thanks for your concern, Paco.
Lots of strange things residing inside one's skull, that's for sure. However, the white "lump" pointed out by the red arrow should *not* be there. It is a tumor ('neuroma') on the hearing and balance nerves. Nature has not made any space available for it and accordingly, it causes -- literally -- headaches, balance impairment, and an increasing loss of hearing. If allowed to grow, it eventually becomes fatal.